Was his departure ever explained?

http://www.dvdtalk.com/reviews/images/reviews/190/1176350080_2.jpg

It's been a long time since I saw the episode but David did guest star on a season 2 episode. He proposed to Ann and she turned him down and he moved to LA.

i really didn't like that character on the show and was just glad to see him go

Actually, I liked David a lot and was disappointed to see him go. Always thought he had great chemistry with Ann, certainly better than any of her future suitors.

I do like the episode in a later season where David comes back and tries to woo Ann back and she is tempted...

If Ann had accepted his proposal, the premise of the show would have been gone.

Remember what happened when Ann married later in the show's run? It ended not long after.

But they saw the writing on the wall--the show was not in its prime anymore, so it was safe to marry off Ann at that point. There was nothing to indicate that she was gonna stay unmarried for the rest of her life. Although Howard Hesseman's character was really quite unremarkable.